Creating Back Link Pages?...good or bad?

Im an HTML/CSS writer learning the practices of SEO.

I have a website built for the Tourist industry, with a client that has about 10 -15 Domains (with very basic very hosting that came with them) that are in some way contain the word “Niagara”…….They are not being used at this time, so I was considering making Back link pages with that contain summarized content related to the Main Site, with a “click here for more info” link. which takes them to the main Website.

Basically taking the Main site content, summarizing and re-wording, one photo or two...as to not have duplicate content.

I’m unclear as to how search engines will react to this, would this be considered “Black Hat” SEO and create negative results? Or is this a legitimate SEO practice?....my concern is how the SEO of Main Business Website will be effected.